Doctor Doctor Who Guide

Last updated 09 January 2020

Part Four

Series Episode Number: 461

World Premiere: Sat 22 Oct 1977 - 6:12pm BST [BBC One] (United Kingdom)
First Broadcast: Fri 13 Jun 1980 - 5:30pm CDT [WTTW 11 Chicago]
Running Time: 21 minutes 22 seconds

8.30 Million (UK)

Appreciation Index: 60 (UK)

Chart Position: 50 () (UK)

Recorded on Tue 26 Apr 1977 in TC6


The Nucleus has escaped the Doctor's body and grown to human size. Its plans to spawn and infect the whole galaxy are nearing fruition. And it looks like K-9 has a new master…